The remarks, made during a series of private speeches to Wall Street banks, seem to offer a rare, unedited glimpse into the foreign policy views of Clinton, who is usually carefully guarded when discussing such topics.

In a 2013 speech to Goldman Sachs, Clinton said if North Korea is able to produce a nuclear-capable intercontinental ballistic missile, it would threaten not just U.S. allies in Asia but also the mainland United States.

“We’re going to ring China with missile defense,” Clinton said. “We’re going to put more of our fleet in the area. So China, come on. You either control them, or we’re going to have to defend against them.”

In a separate speech, Clinton recalled how she issued a blunt warning to her Chinese counterparts over Beijng’s claims to the South China Sea: “You don’t have a claim to all of it,” she said she told them.

The comments do not amount to a shocking revelation. It’s no secret the former secretary of state takes a more hawkish position on China than her former boss, President Barack Obama. But they do reveal flashpoints where existing tensions with China could worsen under a possible Clinton presidency.

Missile defense

One source of military tensions between the two superpowers has been missile defense.

The U.S. in July announced it would deploy an advanced Terminal High Altitude Area Defense, or THAAD, anti-missile system in South Korea. The U.S. insists the system is meant to protect against the growing threat of North Korea’s nuclear and missile programs.

But China, North Korea’s main ally, opposes the deployment, saying THAAD includes radar systems that will be able to track its military capabilities. Beijing also argues the system will destabilize the region and could lead to an arms race.

The U.S. has been careful to avoid any language suggesting that the system is aimed at China, making Clinton’s comments especially noteworthy.

“It’s difficult to interpret this,” says Robert Ross, a U.S.-China relations expert at Boston College and Harvard University. In part, that’s because the THAAD system would not be completely effective against Chinese missiles, he says.

“China’s ability to simply produce more intercontinental ballistic missiles to overwhelm our missile defense system would be relatively easy,” he says, noting that it “costs more to build a missile defense system than it does to build a missile.”

It’s also not clear whether the missile defense strategy has helped the U.S. contain North Korea. Since the announcement of the THAAD deployment earlier this year, China has been even less cooperative with the U.S. on North Korea, Ross says.

South China Sea Territorial Claims

South China Sea

According to speech excerpts, Clinton also made a blunter-than-usual assessment about China’s territorial claims in the South China, where Beijing has overlapping claims with several other countries.

“You can call it whatever you want to call it. You don't have a claim to all of it,” Clinton said, recalling an earlier conversation she had with unspecified Chinese counterparts.

If the U.S. used Beijing’s logic, it could claim “all of the Pacific (Ocean),” according to Clinton. “We liberated it. We defended it. We have as much claim to all of the Pacific. And we could call it the ‘American Sea,’ and it could go from the West Coast of California all the way to the Philippines.”

When told by her Chinese counterpart, “You can’t do that,” Clinton shot back: “Well we have as much right to claim that as you do. I mean, you claim it based on pottery shards from, you know, some fishing vessel that ran aground in an atoll somewhere,” she said.

“You know, we had convoys of military strength. We discovered Japan, for heaven’s sakes,” she said, apparently jokingly referring to U.S. Commodore Matthew Perry’s 19th century mission to forcibly open Japan to trade with U.S. merchant ships.

The U.S. has long said it does not take an official position on the South China Sea disputes, even though it has steadily criticized China’s increasingly aggressive behavior there and expanded defense alliances with Asian countries that have overlapping claims with Beijing.

China response

China has not yet responded to Clinton’s alleged comments, but usually condemns such statements as inappropriate interference in its internal affairs.

China’s President Xi Jinping speaks during the opening ceremony of the G20 Summit in Hangzhou in eastern China's Zhejiang province, Sept. 4, 2016.

“Obviously, China is going to be very unhappy about it,” says Sourabh Gupta, an Asia-Pacific policy specialist at the China-linked Institute for China-America Studies in Washington, D.C.

But Beijing isn’t likely to be surprised. As secretary of state, Clinton often bluntly challenged China’s maritime aggressiveness. She has also been sharply critical of Beijing’s human rights record.

“Her foreign policy and general attitude towards China are a little bit more to the right than President Obama,” Gupta said. “So it’s going to become a slightly tougher and tenser relationship (if she is elected president).”

But Clinton is committed to a continuation of the current trajectory of U.S.-China relations, and that’s not lost on Beijing, Gupta said.

“When she’s actually been in a position of power, she has moderated her positions in such a way that a pragmatic relationship with China can continue,” Gupta said.